How secure is your Android phone or tablet. More specifically, what are your apps able to access? Can they be trusted? What information and features do they have access to? If you have a recent edition of Android you can lock down security and permissions.

An app can potentially access a wide range of information and features on the phone or tablet. These can include the location, the phone, the camera, your contacts, photos and videos, music, text messages, emails and so on.

What an app can do and what it has access to on an Android device depends on a set of permissions. Before Android 6, when an app was installed from the Google Play Store it was given a set of permissions. No-one ever read them and no-one was able to change them afterwards even if they wanted to.

Security and permissions were a bit of a mess.

Then along came Android 6 for a few lucky people with top of the range phones and tablets. Now you have more control over security and permissions that ever before. You can easily see what information and features an app can access and you can revoke permissions at any time.

Let's see how it works on a Samsung Galaxy S6 running Android 6 Marshmallow. You might not have the exact same model of Android phone, but if you have Android 6 then you will have these features somewhere in Settings.

1 Go to Settings

Pull down from the top of the screen and press the gear icon to open Settings. You can also open it from the app drawer where all the apps are listed. Press Application manager.

2 Select an app

No doubt you have dozens of apps and each one might have a different set of permissions. Let's take a look at Facebook, an app that surely everyone has on their phone. Press it in the list of apps.

3 Application info

The Application info screen appears and if you are running Android 6 you will see a Permissions section. Below is a list of things it can access. Here you can see that Facebook can access Calendar, Camera, Contacts and so on. Press permissions.

4 Revoke permissions

All those permissions we saw on the previous screen are now listed and each is given an on/off switch. These now only show what an app is able to do, such as access your contacts, but also you can flip the switch and block access. If you weren't happy with an app having access to your contacts for example, you could set the switch to the off position and it would no longer have access.

It would be a tedious task to go though each of the apps installed on your phone or tablet because many people have dozens or even hundreds. It is certainly possible though and if you wanted, you could customise each app's permissions, revoking access to things you don't want it to access. It is your choice.